### Start TelemetryMetricsPrometheus Application

Source: https://github.com/beam-telemetry/telemetry_metrics_prometheus/blob/main/docs/overview.md

Initiate the TelemetryMetricsPrometheus application during your project's startup. This example shows how to include it in the supervision tree and define initial metrics.

```elixir
def start(_type, _args) do
  # List all child processes to be supervised
  children = [
    {TelemetryMetricsPrometheus, [metrics: metrics()]}
    ...
  ]

  opts = [strategy: :one_for_one, name: ExampleApp.Supervisor]
  Supervisor.start_link(children, opts)
end

defp metrics, do:
  [
    counter("http.request.count"),
    sum("http.request.payload_size", unit: :byte),
    last_value("vm.memory.total", unit: :byte)
  ]

```

--------------------------------

### Add TelemetryMetricsPrometheus to Mix Dependencies

Source: https://github.com/beam-telemetry/telemetry_metrics_prometheus/blob/main/README.md

Add this dependency to your `mix.exs` file to include TelemetryMetricsPrometheus in your project.

```elixir
def deps do
  [
    {:telemetry_metrics_prometheus, "~> 1.1.0"}
  ]
end
```

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